Story highlights

Instagram had racked up more than 30 million users in a year and a half

Photogs say the appeal is in making simple photos look fancy with little effort

Apps like Cinemagram, Piictu, Pixable and Hipstamatic also stand to gain

Facebook's billion-dollar purchase of Instagram this week may have been the first time that many Facebookers heard of the tech-world darling, which lets users turn their phone photos into sleek-looking, stylized images with a single touch.

The acquisition shined a light on what's emerging as a nearly incontrovertible truth in tech circles: Mobile is the future of photography and the tools used to enhance and share phone-generated images have value that is only expected to climb.

Instagram isn't the only player in that field, but it had quickly become its all-star. Barely a year-and-a-half old, Instagram had already racked up 30 million users on Apple's mobile system before opening up to Android users last week. Another 5 million signed up in less than a week, setting the table for Facebook to gobble up what until Monday was emerging as its prime competitor in mobile photo-sharing.

Some early adopters complained that Facebook snatching up their favorite app takes some of the indie shine off of it. But there's no question that, by putting the tool in front of its hundreds of millions of users, Facebook could amp up what's already a quickly emerging sector of the mobile landscape. (For reference, witness what happened with music streaming when Facebook and Spotify signed an exclusive sharing deal).

The appeal of Instagram and similar apps doesn't take much work to suss out: With minimal effort, they let pedestrian photographers share enhanced images with their friends.

JUST WATCHED

Facebook's billion-dollar buy

MUST WATCH

JUST WATCHED

3 things you didn't know about Instagram

MUST WATCH

3 things you didn't know about Instagram02:46

"The strength of Instagram is in its simplicity," said Bill Jones, founder and editor of The Photo Argus, a photography resource blog. "A few clicks and you have a once average image that now looks amazing and can be easily shared with your friends."

Instagram's rapid growth -- it's more than doubled its user base in the past five months -- is just the latest evidence of the explosion of online and mobile photo sharing. In less than two years the app has already hosted more than 500 million images -- more than 30 times greater than the entire photo archive of the Library of Congress.

That sounds like a lot until you realize that Facebook users have uploaded more than 170 billion photos to the social network, making it the single largest host of images on the Internet, according to statistics cited during a panel last month during the South by Southwest Interactive conference.

Photographers on that panel, which included Instagram co-founder Kevin Systrom, said the mobile-photography craze is important, even if it sometimes leads mundane, amateurish images flooding your social networks.

"Having 100 million more photos in the world isn't doing anybody any harm," said Richard Koci Hernandez, assistant professor of new media at the University of California-Berkeley Graduate School of Journalism. "It has value no matter what."

Jones, of The Photo Argus, agrees, and says mobile photography is likely to remain on the rise at technology improves.

"I think this purchase sends a signal that mobile photography is more relevant than ever," he said. "Mobile photography is already overtaking the point-and-shoot market. I think this has been obvious for some time. But soon they will begin to really encroach on the (digital camera) market, as well. As the technology gets better, people might be more inclined to put their 'pro' camera in their pocket instead of purchasing one they need a backpack for."

Instagram is known for producing artful, filter-laden photos that would not look out of place hanging in an art gallery. But Systrom believes the most meaningful images on his network aren't necessarily the ones taken by professional photographers. He cited people in the Midwest who used Instagram earlier this year to document damage caused by tornadoes.

"How can we get the most important images out there -- not necessarily the most socially pleasing?" he said at the SXSW panel, suggesting that Instagram in the future might highlight curated photos, not just the ones with the most "likes."

"How do we sift through that [all the images on Instagram] and present for you the most interesting and most meaningful photos? That's our challenge for the next few years."

"My hope is that people feel at home on Instagram by posting just about anything," Systrom added. "On Instagram, taking photos really helps you see the world around you in a whole new way."

While Instagram has clearly rocketed to the top of the pack in a short time, a rising tide has lifted the ships of other mobile apps as well. Those efforts stand to benefit from the increased attention the Instagram buyout will bring, as well as any Instagram users who may peel off as a sort of nose-thumbing at Facebook, the 800-pound gorilla of the social networking world.

They include:

Cinemagram: Adds animation. With Cinemagram, users are invited to shoot a few seconds of video with their phones. Then, by selecting a few images from their videos, they can create what appear to be animated photographs. We're pretty sure this is how they did it at Hogwarts.

Piictu: In a way, Piictu is the anti-Instagram. Users are encouraged to post plain, simple photos that communicate for them -- which is why the app has been called "Twitter for pictures." Like Twitter, photos are grouped together under trending topics, letting users share with strangers as well as friends.

PIxable: If Instagram is a way to push your fancy, filtered photos to sites like Facebook and Twitter, Pixable lets you take photos already on those sites, fancy them up and share with other users of the app.

Hipstamatic: A precursor to Instagram, Hipstamatic was probably the first way people started seeing grainy, old-fashioned photos popping up in their Facebook and Twitter feeds. Instead of instantly applying a filter, Hipstamatic lets users modify their photos through a series of tweaks to get just the right classic look.